Glow-worm
Glow-worm Thermocouple S900001
Glow-worm S900001 thermocouple for Glow-worm back boiler units, a pilot flame sensing part that keeps the burner lit safely.
At a glance
- Part type: Thermocouple
- Also known as 1336662
- This part is fitted to a gas appliance; installation must be carried out by a Gas Safe registered engineer.
£38.99
£32.49 ex. VAT · VAT at 20%
Same-day dispatch
Ordered by 4pm Mon–Fri, 10:30am Sat.
30-day returns
Unused, in original packaging.
What it is
The Glow-worm S900001 is a thermocouple supplied for Glow-worm back boiler units. It sits in the pilot flame path and generates the small voltage that holds the gas valve open while a flame is present, so the burner can run and the appliance shuts down safely if the pilot goes out. The part is listed under the Vaillant Group spares range and is used across a number of older Glow-worm back boiler models.
Signs this part needs replacing
- The pilot flame lights but will not stay alight once the control knob is released.
- The pilot goes out repeatedly during normal running, or the appliance drops out shortly after ignition.
- The main burner will not fire even though a pilot flame is visible.
- The thermocouple tip is blackened, sooty, corroded or visibly damaged.
- The appliance locks out and needs repeated manual resetting to run.
Before you order
- Check the GC number and model on the appliance data badge against the compatibility list before ordering.
- Cross-reference the previous numbers 411638 and 900001, and the alternative number 1336662, against the part you are removing.
- This part is fitted to a gas appliance; installation must be carried out by a Gas Safe registered engineer.
Mechanical
| Part type | Thermocouples |
|---|---|
| Length | 0.1mm |
| Width | 0.1mm |
| Depth | 0.1mm |
Compliance
| Manufacturer part number (MPN) | S900001 |
|---|---|
| GC number | 392-934 |
| Barcode / EAN | 4024074501443 |
| GPC classification | Household Boilers/Furnaces/Tank Water Heaters Replacement Parts/Accessories |
| Alternative numbers | 411638, 900001, 1336662 |
| Make | Model / assembly | Reference | Years | Fitment |
|---|---|---|---|---|
| GLOWWORM 45 BACK BOILER UNIT | 44-315-27 | 44-315-27 | — | — |
| GLOWWORM 45F BACK BOILER UNIT | 44-315-29 | 44-315-29 | — | — |
| GLOWWORM 52 LPG BACK BOILER UNIT | — | — | — | |
| GLOWWORM 52F BACK BOILER UNIT | — | — | — | |
| GLOWWORM 56 BACK BOILER UNIT | 44-315-28 | 44-315-28 | — | — |
| GLOWWORM 56F BACK BOILER UNIT | 44-315-30 | 44-315-30 | — | — |
| GLOWWORM GLOWWORM 45 BBU | — | — | — | |
| GLOWWORM GLOWWORM 45/4F BBU | — | — | — | |
| GLOWWORM GLOWWORM 56 BBU | — | — | — | |
| GLOWWORM GLOWWORM 56F BBU | — | — | — |
Showing 10 of 44 compatible appliances.
Documents & drawings
Everything we hold for this part. Where a document exists but we don't hold it, the technical team will source it from the manufacturer — usually the same working day.
GLOWWORM appliance manual — HIDEAWAY 100 BF (GC 41-313-26)
manualmanualGLOWWORM appliance manual — HIDEAWAY 100 OF (GC 41-313-27)
manualmanualGLOWWORM appliance manual — HIDEAWAY 120 BF (GC 41-313-28)
manualmanualGLOWWORM appliance manual — HIDEAWAY 120 OF (GC 41-313-29)
manualmanualGLOWWORM appliance manual — HIDEAWAY 40 BF (GC 41-313-16)
manualmanualGLOWWORM appliance manual — HIDEAWAY 40 OF (GC 41-313-17)
manualmanualGLOWWORM appliance manual — HIDEAWAY 50 BF (GC 41-313-14)
manualmanualGLOWWORM appliance manual — HIDEAWAY 50 OF (GC 41-313-15)
manualmanualGLOWWORM appliance manual — HIDEAWAY 60 BF (GC 41-313-12)
manualmanualGLOWWORM appliance manual — HIDEAWAY 60 OF (GC 41-313-13)
manualmanualGLOWWORM appliance manual — HIDEAWAY 70 BF (GC 41-313-24)
manualmanualGLOWWORM appliance manual — HIDEAWAY 70 OF (GC 41-313-25)
manualmanualGLOWWORM appliance manual — HIDEAWAY 80 BF (GC 41-313-24)
manualmanualGLOWWORM appliance manual — HIDEAWAY 80 OF (GC 41-313-25)
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